This invention relates to the design of a shipment pallet for heavy and sensitive electronic equipment. The purpose of the shipment pallet is to reduce the distribution environment's shock and vibration force levels (g's) below the break points of the equipment so that the equipment will arrive at its destination functionally operational and cosmetically intact.
Prior art dictates the use of cushioning material to moderate the shocks and vibrations incurred in the distribution system (i.e. trucks, trains, airplanes, ships). As illustrated in FIG. 1, this is done by adding a cushioning layer 21 between two top deck boards 22 and 23 or as illustrated in FIG. 2, adding the cushioning layer 21 between the top of the stringers 24 and the top deck board 22. The performance of the cushioning material is published by the cushion manufacturer and the designer calculates the density and amount of material required in the design.
When designing cushions for packaging, there is a trade-off between shock and vibration. When a cushion is designed that will lower the destructive g's for shock, the vibration g's increase. In the lower g ranges for shock (15g's-35 g's), this inverse sensitivity amplifies and any minor reduction in the shock g's results in a major increase in the vibration g's.
Quite often, the engineer can design a cushion that will reduce the shock g's below the break point of the equipment only to fine out that he has inadvertently raised the vibration g's above the allowable limit, thus destroying the equipment with vibration damage in the distribution system. When the vibration problem is solved using a stiffer, more dense cushion, the shock g's are corresponding increased causing shock damage. When the shock damage is resolved by using a softer, less dense cushion the vibration g's are increased causing the vibration damage again. The cycle goes on and on with the engineer bouncing back and forth between solving shock damage and incurring vibration damage and solving vibration damage while incurring shock damage. As you can see, there was a bottom limit to any cushion design the engineer could create which was bound by this inverse relationship between shock and vibration.
In the art today, there is a need for a packaging shipment pallet for large and sensitive equipment that will be able to reduce the shock g's g without incurring a resulting increase in vibration g's.